The Deterrence Index addresses the extent to which policies are a deterrence for asylum seekers. The Index seeks to quantify cumulatively the resulting mix of countries’ changing asylum rules. Five key deterrence measures have been considered from three areas: Three sets of instruments are included: (1) access control policy, which refers to the rules and procedures governing the admission of foreign nationals and its instruments include visa policy, regulations for carriers, safe third country provisions, etc. In this area, the deterrence measure refers to the introduction of so-called ‘safe third country’ provisions, which mean that persons seeking asylum in country A will be refused entry into that country, if on their way to country A, they have travelled through state B, a country which country A regards as a ‘safe country’ and in which the asylum seeker could have applied for asylum. (2) asylum determination procedures. Rules concerning determination procedures relate to entry into a country's refugee recognition system, appeal rights, and rules concerning protection that is subsidiary to the rather narrowly defined Geneva Convention criteria for full refugee status. In this area, the deterrence measure refers to rules concerning the granting of subsidiary protection status which allow asylum seekers to remain in a country of destination even though their application for full refugee status under the Geneva Convention is refused. (3) migrant integration policy. policy is concerned with rights and benefits given to asylum seekers inside a country of destination. Here measures are: freedom of movement vs. a compulsory dispersal policy; cash welfare payments vs. a system of vouchers; and third, the right to work under certain conditions vs. a general prohibition to take up employment as an asylum seeker. Policy-makers can introduce changes in the regulations in these three areas in an attempt to raise the deterrence effect of their policy, which in turn is expected to make their country less attractive to asylum seekers in relative terms. The dataset includes scores for 17 OECD countries for 1985 and 2000. To calculate the index, the researcher analysed two sets of annual yearbooks, the OECD’s ‘Trends in International Migration’ (SOPEMI) and the US Committee for Refugees’ ‘World Refugee Survey’ for the years 1985–2000. For each of the five measures, Thielemann creates a dummy variable (value 1 value whether a measure was in operation in a country). The aggregation is additive, with no weighting applied.